Exhaust silencer



HERRING AL EXHAUST SILBNCER Filed May 20" 1930 Invert [or A llorhy Vim roved mufller,

Patented Dec. 29 1931' UNITED STATES PATENT OFFICE VBILLINGS, MONTANA Exnus'r sILmwEB.

A Amie-am flledullay 2c, 1930. [serial no. 454,034. 1

short tubular shell 13 which shell 13 is pro- 7 vided on its periphery with a plurality of This invention relates to exhaust mufllers or sllencers of the kind commonly used in connection with internal combustion engines to reduce or eliminate the noise caused bythe engine exhaust;

A primary object of this invention is to important object of the invention being to provide. an exhaustmufiler; especlallg designed for reducing backpressure an heat caused therefrom, and further to reduce fuel consumption whichis increased due to back pressure in an exhaust mufller.

Other objects and advantages of the invention will become apparent during a study of the following description, taken in connection with the accompanying drawings wherein: a V I y y F gurel 1s a side elevational view of our igure 2 is a therethrough,

Figure 3 is a transverse section taken sublongitudinal sectional view stantiallyon the line 33 of Figure 2,

Figure 4: is a similar view taken substantially on the line4:4 of Figure 2.

With reference more in detail to the drawings it will be seen that our improved silencer or muflier comprises an outer'shell or casing 5 tapering toward one end as at 6 to provide a vacuum chamber'7. At said one end, inwardly of'the chamber 7 there is secured within the casing 5 an end plateor head 8.

Arranged within the other end of the casing 5 is a conical mouth 9 constituting an air intake, and at its apex said conical mouth 9 extends through a central opening arranged in an end plate or head 10. At said apex, said mouth 9 is telescopically received within one end of a cylindrical shell or tube -11 which extends longitudinally through the casing 5 and at its forward end projects through a suitable opening formed in the end or head 8 to terminate inwardly of the vacuum chamber 7.

portions of the tubular shell 11 is a relatively openings 14. That end of the shell remote .from the air intake mouth 9 is provided with an outstanding annular flange so shaped as to provide an internal groove 15. Arranged betweentthe casing 5 and the tube 11 is an elongated conical shell 16, which shell 16' has itslarg'est end integralwith the end platelO, the shell gradually tapering tohave itsapex integral with-the end plate or head 8;

The conical shell 16 forms with the cylin drical shell 13 a substantially conical sound deadening chamber S into which the exhaust gases from theinternal combustion engine pass from exhaust" pipes E which pipes lead fromthe internalcombustion engine and are passed through suitable openings 17 in the conical mouth 9 and openings 18 in the head a or endplate 10. V i a At their discharge ends, the exhaust pipes E are flattened or fan shaped as at 19, the

WILLIAM E. nnnnme, or ALBERT LEA, mnmnso'ra, AND EARL R. HEBRING, or

flattening of the dischargeiendof said pipes" I E being'such as not to decrease the end area ofthe pipes.

From the sound deadening chamber S the a exhaust gases escape through a passage P vformed by the tube 11 and cylinder 13 to pass through apertures or perforations 19 formed inthe wall of the conical shell 16 forwardly of the cylinder 13 into the main chamber M. From the ,main chamber M, the gases pass through perforations 20 in the end plate or head 8 into the vaccum chamber 7 toexhaust 'from thesilencerthrough the exhaust opening 21 at the smallest end of the chamber 7. r 'Air or wind passing into the air intake mouth 9 andfiowing in the direction of the arrows in Figure 2, through the air tube 11 "and vacuum chamber? in said vacuum chamber creates a vacuum in the lower part of the vacuum chamber 7 thereby drawing the exhaust gasesout of the said sound deadening {chamber S, through passage fP into main chamber MYand finally into the vacuum chamber 7 to exhaust through the opening i 21in the end of the: silencer or muflier. Circumj acent and intermediate the end The vacuum created in the chamber 7 has a inlet pipes entered in the exhaust pipe E thereby de creasing and eliminating back pressure.

Of course, it is to be understood that the wind or air entering into the air tube 11 through the conical mouth 9 is either by natural or mechanical causes depending on whether the mull'ler is to be used on internal combustion engines in the air or on the ground or in other words for example on an automobile or on an aeroplane.

From the foregoing then it will be seen that the hottest gases will pass through the silencer between the outer casing 5 and the conical member or shell 16, that is in the main chamber M and consequently the hot gases in said chamber are cooled by the sur rounding atmosphere.

The gases in the sound deadening chamber S will also be cooled by the air passing through the air tube 11 so that a muiiler embodying the features of the present inventi on will extract heat from the burned gases from the time the burned gases enter until they exhaust from the muliier, the volume of the burned gases being decreased by the cooling above referred to.

It will be further noted that there are two E for the burned gases from the engine, so that the gases from the cylinders on each side of a vertical line drawn through the center of the engine are collected and carried down through and under the fuselage when the invention is used in conjunction with aeroplanes, in two separate pipes.

This position of the mulller is best for decreasing accidents in the event the muffler should work loose from the aeroplane at such time it being obvious that the mulller will drop away from the plane and the only possible resulting damage being the possibility of a bent tail skid.

Thus it will be seen that we have produced a type of mulller that will keep the engine from overheating caused by back pressure and secondly will destroy sound caused by the exhaust of the internal combustion engine. Such result will permit of a reduction in the expense of the sound proof construction on aeroplanes.

livenv though we have herein shown and described the preferred embodiment of our invent-ion, it is to be understood that the .same is susceptible to changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

Having thus described our invention, what we claim as new is:

1. A mufiler comprising an outer casing, end plates arranged in .said casing, a tube extending between end plates, a conical shell circumjacent said tube and having its smallest end terminating adjacent one of said end plates, a relatively short cylinder interposed between said tube and said conical shell and spaced respectively therefrom, and provided at one end with an annular flange bridging the space between said cylinder and conical .shell, said cylinder, said conical shell intermediate said flange and said one end late, and said one end plate respectively eing perforate.

2. A muffler for internal combustion engines comprising an outer casing provided with an inlet at one end, and an outlet at its opposite end, spaced end plates mounted in said casing, an open ended tube extending between said end plates, a conical shell disposed'about said'tube and having its widest end contacting with one end plate, and its smallest end contacting with the other of said end plates, at relatively short cylinder arranged concentrically of the tube and pro vided with a flange at one end for bridging the space between said cylinder and said conical .shell, said cylinder providing with a corresponding portion of said conical shell a.

sound deadening chamber, said cylinder be-l, mg apertured, and spaced from said tube to,

provide therewith a passage affording com munication between said sound deadening chamber and the space between said tube and conical shell provided between said flange and said one of said end plates, said conical shell intermediate said flange and said other end plate, and said other end plate, respectively, oeing perforated whereby the exhaust gases from said sound deadening chamber may pass from said chamber into the space between said conical shell and said outer casing to subsequently pass outwardly of said casing at said outlet of said casing.

In testimony whereof we affix our signatures.

WVILLIAM E. I-IERRING. EARL R. HERRING. 

